Malicious PDF — malware analysis report

Static analysis result for SHA-256 df27e55a2dfa2587…

MALICIOUS

PDF

82.7 KB Created: 2021-09-05 04:20:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 0c5731235e3c44e36542ca7fdd080d54 SHA-1: cbbb6fe42b7c454d8e8518a76ebca87f2b2c0da0 SHA-256: df27e55a2dfa25878d0b19be9cb0bc8591b1de6820ae50394a9bb4b94970a107
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://fmi.lu/userfiles/files/mejukurabivo.pdf In PDF document text
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/9dc7b475c43a34b1c9968e798394482b/62878141905.pdfIn PDF document text
    • https://area5srl.it/file/kilanivujizotamobo.pdfIn PDF document text
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/13d4aa630fc1158121342428426389c4/wogiz.pdfIn PDF document text
    • http://lnyuanzong.com/uploads/files/20210626035503.pdfIn PDF document text
    • https://abicecream.ru/ckfinder/userfiles/files/13506277813.pdfIn PDF document text
    • http://saiprogetti.net/userfiles/files/bifusagixabufa.pdfIn PDF document text
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085d15c57e91---88057430860.pdfIn PDF document text
    • http://vhktn.at/images/content/files/22460569685.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161091dc121fda---jidolegofurunipasaw.pdfIn PDF document text
    • https://abcoegypt.com/userfiles/files/13499530002.pdfIn PDF document text
    • http://neboskreb-irk.ru/uploads/userfiles/files/78251726787.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/450bdd7ead6cae6845551b71857e14ce/xegeta.pdfIn PDF document text
    • http://avs-market.ru/admin/ckfinder/userfiles/files/wovepowul.pdfIn PDF document text
    • http://zulassungsservice4you.de/bilder/file/30881437184.pdfIn PDF document text
    • https://hotnews.md/upload/userfiles/files/89506838739.pdfIn PDF document text
    • http://cnsgawefgl.netsociality.com/upload/files/pezutefidibevutinema.pdfIn PDF document text
    • http://mspchicagolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/69000551456.pdfIn PDF document text
    • http://sumisaedu.com/FileData/ckfinder/files/20210713_8307F0F88DD24766.pdfIn PDF document text
    • http://mijn-nederland.nl/userfiles/file/38016783614.pdfIn PDF document text
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d9b2f71daa---jamolobopezerobapib.pdfIn PDF document text
    • http://myblindz.com/fck_user_files/file/13133729761.pdfIn PDF document text
    • https://vendax.ro/files/file/dizawejubulironoxor.pdfIn PDF document text
    • https://irrisyst.eu/files/file/29193070553.pdfIn PDF document text
    • http://cuacongtudongbinhduong.com/upload/files/fuwezobolijuwasonikofuzup.pdfIn PDF document text
    • http://aptchasers.com/FCKeditor/userfiles/file/gomanupujurane.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=hp+tet+arts+syllabus+2019+pdfPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dcb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCB6 17888 bytes
SHA-256: 7cbccb101ba9d7280db0aa09542fd6d423f6c9ba41714cd79844fc2571fbee90
font_01_sfnt_off00010b80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B80 10980 bytes
SHA-256: d1c8cd4ae9091d963b8074aca3342067611b0fb82a088d2d4741a4022c1fc282
font_02_sfnt_off0001250a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1250A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1